(a) Field of the Invention
The present invention relates to a novel faujasite aluminosilicate and a method of producing the same and, more particularly, to a faujasite aluminosilicate which may be suitably used in the field of catalysts or the like and a practically advantageous method of producing the same.
Further, the present invention relates to a hydrocracking catalyst for heavy hydrocarbon oils which contains the faujasite aluminosilicate as a catalyst carrier and is so excellent in catalytic properties as to effect the hydrocracking of heavy hydrocarbon oils with high efficiency and an increased yield of light hydrocarbon oils including gas oil, kerosine, and naphtha.
(b) Description of the Related Art
In recent years, the proportion of heavier crude oils is increasing in the worldwide supply of crude oils, and at the same time, the nature of the demand for petroleum fractions is changing, thereby causing a tendency for light hydrocarbon oils to be in short supply and a tendency for heavy hydrocarbon oils to be in excess. Under these circumstances, there have been developed techniques for cracking heavy hydrocarbon oils to convert them to light hydrocarbon oils such as naphtha, kerosine, and gas oil. Among these techniques, hydrogenation treatment techniques such as hydrocracking and hydrogenation refining are very promising because of the capability of producing light hydrocarbon oils of high quality. Therefore, studies for developing effective catalysts for the hydrogenation treatment have recently been actively made, and particularly, there have been many studies and propositions for the use of zeolite catalysts.
The use of usual zeolites for the hydrocracking of heavy hydrocarbon oils however causes enormous generation of coke because of their too high acidity, resulting in rapid deactivation. Also, it is undesirable because the cracking proceeds excessively to generate a considerable amount of gaseous hydrocarbons.
In order to solve these problems, there have been proposed some methods in which zeolites are treated with steam at an appropriate temperature to inhibit the generation of coke and the excessive cracking and the resulting steamed zeolites are subjected to acid treatment to control the acid content, thereby improving the activity (Japanese Patent Application Kokai Koho (Laid-open) No. 58-147495, Japanese Patent Application Kokai Koho (Laid-open) No. 62-297389). Nevertheless, further improvement is necessary to put thus improved conventional zeolites to practical use because, when used for the selective hydrocracking of heavy hydrocarbon oils as described above, they do not satisfy all the requirements for catalytic life, the selectivity for light hydrocarbon oils, and catalytic activity and, in addition, the catalytic effectiveness such as catalytic activity and catalytic life are largely influenced by the physical properties of the steamed zeolites to be subjected to acid treatment and acid treatment conditions.